MUMBAI, India 
Mumbai's businessmen will now be getting ads delivered with their home-cooked lunches.

Some 5,000 of the city's famed lunch box delivery men – or dabbawallas – have traded their loose shirt-and-trouser uniforms for T-shirts advertising a mutual fund.

Rather than eating out at restaurants many of Mumbai's office workers pay to have a cooked meal delivered from their homes. Getting those meals to the city's army of office workers is the job of the dabbawallas, who deliver to some 500,000 customers each day.

Jaideep Bhattacharya, the head of marketing at UTI Asset Management, said the delivery men were the perfect way to advertise the company's mutual fund at a time when finances were strained.

"We found the dabbawallas a great way to reach our target audience at the lowest possible cost," he said Thursday.

It's also a boon for the dabbawallas, who have become an integral part of Mumbai's landscape, often seen on bicycles and trains balancing wooden crates filled with lunch boxes on their heads.

Other companies have also expressed interest in the advertising, said Shopan More, president of the Dabbawallas' Association.

"Our main business is delivering lunch," More said. "But of course since there is so much interest, we will do it."